Novel Stemless Hip Prosthesis Design and Finite Element Analysis to validate stemless Prosthesis for Reduction of Aseptic Loosening in Total Hip Arthroplasty

Total Hip Arthroplasty/ Replacement is a major corrective procedure involving replacement of femoral head and neck of the long bone connected to the pelvis. Conventional methods involved using long stemmed Titanium Alloy (Ti6Al4V) implants with a Cobalt-Chrome (Co-Cr) spherical caps. The invasiveness, large distributions of interfacial stresses induce stress shielding and bone resorption leading to loosening and painful remission surgeries specifically in the younger more active individuals. The need to improve upon the less invasive stemless models in warranted. This paper incorporates an improved novel design to a stemless hip prosthesis. Finite element analysis concluded average stresses of 9MPa, average strains of 0.0063 mm/mm, total deformation of 88mm all within comparable ranges and better than conventional long-stemmed models as prosthesis for an exaggerated point load of thrice the body weight of human (867N) taken redundantly. Fatigue life is better than conventional models crossing 1010 cycles for the extreme loading. The contact stresses also proved to be lesser and spread over a smaller area reducing the chances of aseptic loosening compared to conventional models.

Download Full-text

Total hip arthroplasty-finite element analysis validation

10.1109/nebc.1990.66265 ◽

2002 ◽

Author(s):

D. Leone ◽

L. Breglia ◽

J. Gander ◽

J. Ibets ◽

C. Teeling ◽

...

Keyword(s):

Finite Element Analysis ◽

Finite Element ◽

Total Hip Arthroplasty ◽

Hip Arthroplasty ◽

Element Analysis ◽

Total Hip

Download Full-text

Metaphyseal anchoring short stem hip arthroplasty provides a more physiological load transfer: a comparative finite element analysis study

10.21203/rs.3.rs-53386/v2 ◽

2020 ◽

Author(s):

Shuang G Yan ◽

Yan Chevalier ◽

Fanxiao Liu ◽

Xingyi Hua ◽

Anna Schreiner ◽

...

Keyword(s):

Finite Element Analysis ◽

Finite Element ◽

Total Hip Arthroplasty ◽

Hip Arthroplasty ◽

Load Transfer ◽

High Stress ◽

Short Stem ◽

Von Mises Stress ◽

Element Analysis ◽

Total Hip

Abstract Background: Short stem total hip arthroplasty (SHA) preserves femoral bone stock and is supposed to provide a more natural load transfer compared to standard stem total hip arthroplasty (THA). As comparative biomechanical reference data are rare we used a finite element analysis (FEA) approach to compare cortical load transfer after implantations of a metaphyseal anchoring short and standard stem in native biomechanical femora. Methods: The subject specific finite element models of biomechanical femora, one native and two with implanted metaphyseal anchoring SHA (Metha, B.Braun Aesculap) and standard THA (CLS, Zimmer-Biomet), were generated from computed tomography datasets. The loading configuration was performed with an axial force of 1400 N. Von Mises stress was used to investigate the change of cortical stress distribution. Results: Compared to the native femur, a considerable reduction of cortical stress was recorded after implantation of SHA and standard THA. The SHA showed less reduction proximally with a significant higher metaphyseal cortical stress compared to standard THA. Moreover, the highest peak stresses were observed metaphyseal for the SHA stem while for the standard THA high stress pattern was observed more distally. Conclusions: Both, short and standard THA, cause unloading of the proximal femur. However, the metaphyseal anchoring SHA features a clearly favorable pattern in terms of a lower reduction proximally and improved metaphyseal loading, while standard THA shows a higher proximal unloading and more distal load transfer. These load pattern implicate a reduced stress shielding proximally for metaphyseal anchoring SHA stems and might be able to translate in a better bone preservation.

Download Full-text

Short stem hip arthroplasty provides a more physiological load transfer: a comparative finite element analysis study

10.21203/rs.2.23711/v1 ◽

2020 ◽

Author(s):

Shuang G Yan ◽

Yan Chevalier ◽

Fanxiao Liu ◽

Xingyi Hua ◽

Anna Schreiner ◽

...

Keyword(s):

Finite Element Analysis ◽

Finite Element ◽

Total Hip Arthroplasty ◽

Hip Arthroplasty ◽

Load Transfer ◽

High Stress ◽

Short Stem ◽

Von Mises Stress ◽

Element Analysis ◽

Total Hip

Abstract Background: Short stem total hip arthroplasty (SHA) preserves femoral bone stock and is supposed to provide a more natural load transfer compared to standard stem total hip arthroplasty (THA). As comparative biomechanical reference data are rare we used a finite element analysis (FEA) approach to compare cortical load transfer after implantations of a cementless short and standard stem in native biomechanical femora.Methods: The subject specific finite element models of biomechanical femora, one native and two with implanted SHA (Metha, B.Braun Aesculap) and standard THA (CLS, Zimmer-Biomet), were generated from computed tomography datasets. The loading configuration was performed with an axial force of 1400 N. Von Mises stress was used to investigate the change of cortical stress distribution.Results: Compared to the native femur, a considerable reduction of cortical stress was recorded after implantation of SHA and standard THA. The SHA showed less reduction proximally with a significant higher metaphyseal cortical stress compared to standard THA. Moreover, the highest peak stresses were observed metaphyseal for the SHA stem while for the standard THA high stress pattern was observed more distally.Conclusions: Both, short and standard THA, cause unloading of the proximal femur. However, SHA features a clearly favorable pattern in terms of a lower reduction proximally and improved metaphyseal loading, while standard THA shows a higher proximal unloading and more distal load transfer. These load pattern implicate a reduced stress shielding proximally for SHA and might be able to translate in a better bone preservation.

Download Full-text